As a person who really loves Trophy's (Just got my 34th Platinum today). I must say that I really wish developers would start using them in a better fashion. Mining X, Killing X, and Crafting X amounts of enemies/gear/items is not something that deserves a reward. A lot of these will require you to be max and then put much more effort in that is required. The real achievement is hitting max. Just because you craft/mine/kill more than another player doesn't make you any better.
Obviously i'm not saying that I don't want achievements that take forever to accomplish (because I definitely do). However spamming buttons mindlessly for hundreds of hours is not the way to do it. I would rather see achievements like this (and I do believe some are already implemented):
Complete every Quest in each area/ALL Areas.
Complete the Main Scenario.
Down Ifrit/Moogle King/Batraal/ or Kill them within a specified time
Craft every item related to your class/All Classes.
Gather every item related to your class/All Classes.
Pull off a certain amount of damage (Ex. 666, or 3000)
Complete a certain amount of Crafting/Battling/Gathering leves.
Down every possible mob type in the game
Down every NM
Visit every area
All jobs max
That's how I would do it at least. Crafters/Gathers who have 50 already are screwed in this situation. The spam X achievements are the ones I will never do because they simply aren't worth the time/effort. I would rather enjoy the game than despise it.